The BIOSTATISTICS CORE will provide biostatistical and data management support to the clinical, basic science, and developmental research cores. This support will include: (i) collaborating on study design, sampling plans, endpoint definitions randomization schemes and determination of sample size; (ii) designing, composing and printing of standardized cross- study case-report forms to be used for all patients enrolled in studies carried our by the collaborative group; (iii) preparing protocol-specific case-report forms for each study; (iv) training clinical and laboratory staff on data collection procedures; (v) centralizing enrollment (and randomization, as required) of patients into studies using a toll-free telephone line; (vi) establishing procedures for regular transmission of data collection forms via fax and other data by electron mail; (vii) developing a specimen tracking system; (viii) central data entry and computer editing of data (ix) central data management using commercial software well-suited for the maintenance of a large number of databases; (x) preparing of regular reports to data originators on errors and missing data on each case report form; (i) preparing regular reports on enrollment and patient characteristics, and on completeness of follow-up for follow- up studies; (xii) data analysis, both interim and final, for study reports; and (xiii) research on statistical methods to enhance the scientific investigations carried out by the collaborative group. Dr. Neaton, Ms. Wentworth, and Mr. DuChene of the Division of Biostatistics in the School of Public Health at the University of Minnesota have served as statistical center of a number of NIH-sponsored research projects.